Flash memory is an electronic (solid-state) non-volatile computer storage medium that can be electrically erased and reprogrammed. The NAND flash memory is a main type of flash memory named after the NAND logic gates, it has advantages of fast programming and short erasing time.
In NAND flash memory, the memory array is made of a large amount of memory units. Each memory unit stores a binaural data 0 or 1. Usually the memory units are arranged as an N×M array, which means a plurality of disks compose one memory array and used as a single disk. It stores data in strings in different disks. When data is accessed, related disks in the array are operated together, which reduces the data access time and improves the space usage.
With the widespread of NAND flash memory, data leakage become a serious problem. In view of this, it is necessary to develop destroy scheme to avoid information leakage.